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Georgia Tech
School of Aerospace Engineering
Aerospace Systems Engineering
A Modern Approach
Dr. Daniel P. Schrage
Professor and Director,
Center of Excellence in Rotorcraft Technology(CERT)Center for Aerospace Systems Analysis (CASA)
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Georgia Tech
School of Aerospace Engineering
Course Materials
Primary Text, Dieter, !Engineering Design"
A #aterials and Processing Approach$, %rd
Edition, #c&ra' ill, ***
Secondary Text,$Systems Engineering
+ndamentals$ Defense Systems
#anagement College, -/
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Georgia Tech
School of Aerospace Engineering
The Prodct Design Process
(Chapter -, Dieter)
0ntrodction and 0mportance of Prodct Design
The Design Process 1 A Simplified Approach
Considerations of a &ood Design
Detailed Description of Design Process
#ar2eting
3rgani4ation for Design
Compter5Aided Engineering
Designing to Codes and Standards
Design Re6ie'
Technological 0nno6ation and the Design Process
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Georgia Tech
School of Aerospace Engineering
Some Important Concepts Design" ! to fashion after a plan$ (7e8ster Dictionary)
lea6es ot the essential fact that to design is to createsomething that has ne6er 8een
Synthesis" !plling together$
A8ility to design is 8oth a scienceand an art
The science!can 8e learned$ throgh techni9es : methodsThe artis 8est !learned 8y doing$ design
Discovery" !getting the first sight of, or the first 2no'ledge of
something$, as 'hen Colm8s disco6ered America
Invention" re9ires the design 8e a step 8eyond the limits ofexisting 2no'ledge (8eyond the state of the art). Some designs
are trly in6enti6e, 8t most are not
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Georgia Tech
School of Aerospace Engineering
Aerodynamics Economics
Propulsion
Safety
Aerodynamics
S&C
Propulsion
Performance
Manufacturing
Economics
Safety
Structures
Manufacturing
Structures Performance
Conceptual Design Tools(First-Order Methods)
Synthesis & Sizing
Preliminary Design Tools(Higher-Order Methods)
Geometry
Mission
IncreasingSophistication andComplexity
Approximating FunctionsDirect Coupling of Analyses
Integrated RoutinesTable Lookup
Integrated Synthesis and AnalysisVarying Fidelity of Synthesis, Sizing& Analysis
S&C
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Georgia Tech
School of Aerospace Engineering
Good Design requires both Synthesis & Analysis
Typically, 'e approach complex pro8lems li2e design 8ydecomposing the pro8lem into managea8le parts orcomponents1 ;ecase 'e need to nderstand ho' the part 'ill perform in ser6ice
'e mst 8e a8le to calclate as mch a8ot the part
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Georgia Tech
School of Aerospace Engineering
The our Challenges !C"s# of the
Design En$ironment Creati$ity1 Re9ires creation of something that has not existed 8efore
or not existed in the designer
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Georgia Tech
School of Aerospace Engineering
roduct Design rocess Engineering design process can 8e applied to se6eral
different ends
1 Design of roducts, 'hether they 8e consmer goods
and appliances or highly complex prodcts sch as
missile systems or >et planes
1 Another is a comple% engineered systemsch as anelectric po'er generating station or a petrochemical
plant
1 ?et another is the design of a building or bridge
The principles and methodology of design can 8e sefllyapplied in each of these sitations. o'e6er, the emphasis
in Dieter
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Georgia Tech
School of Aerospace Engineering
Dieter"s 'oo( Goal
Pro6ide insight into the crrent 8estpractices for doing prodct design
The design process shold 8e condcted soas to de6elop 9ality cost5competiti6e
prodcts in the shortest time possi8le 0s necessary, 8t insfficient for Aerospace
Systems Design
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Georgia Tech
School of Aerospace Engineering
)apanese Auto Industry and The *+S+ Auto Industry
90%
Total Japanese
Changes Complete
U.S. Company
Japanese
Company
20-24
M
onths
14-17
M
onths
1-3
M
onths
Job#
1
3
M
onths
Num
berofEngine
ering
Product
ChangesProcessed
Japanese/U.S. Engineering Change Comparison
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Georgia Tech
School of Aerospace Engineering
The ,uality Engineering rocess
pro$ides -ecomposition Methods & Tools
Customer
Quality
FunctionDeployment
Off-Line
Quality
FunctionDeployment
Off-Line
Seven
Managementand Planing
ToolsOff-Line
Seven
Management
and Planing
ToolsOff-Line
Statistical
ProcessControl
On-Line
Statistical
ProcessControl
On-Line
Roust
Design Met!ods"Taguc!i# Si$ -
Sigma# DO%&Off-Line
Roust
Design Met!ods
"Taguc!i# Si$ -
Sigma# DO%&Off-Line
'no(ledge Feedac)
*+eeds*,dentify
,mportant
,tems
*ariation
%$periments
*Ma)e
,mprovements
*.old /ains
*Continuous
,mprovement
!a"#ng hea$ the &"o#'e o( the ')stome$*+ ,- p$#o$#t#/es he$e#mp$o"ements a$e neee1 Tag)'h# p$o"#es the me'han#sm (o$#ent#(y#ng these #mp$o"ements
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Georgia Tech
School of Aerospace Engineering
Traditional Design & De$elopment *sing only a Top
Do.n DecompositionSystems Engineeringrocess
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Georgia Tech
School of Aerospace Engineering
IPPD Environment for System Level Design Trades andCycle Time Reduction
S/STEM
-0CESS
-EC0M0SITI01
S/STEM
*1CTI01A2
DEC0M0SITI01
C0M01E1T
*1CTI01A2
DEC0M0SITI01
C0M01E1T
-0CESS
-EC0M0SITI01
A-T
-0CESS
-EC0M0SITI01
A-T
*1CTI01A2
DEC0M0SITI01
roduct
Tradesrocess
Trades
roduct
Trades
rocess
Trades
-E2IMI1A-/
DESIG1
!A-AMETE-#
-E2IMI1A-/
DESIG1
!A-AMETE-#
DETAI2
DESIG1
!T02E-A1CE#
DETAI2
DESIG1
!T02E-A1CE#
MA1*ACT*-I1G
-0CESSES
C01CET*A2
DESIG1!S/STEM#
rocess
Trades
I1TEG-ATED
-0D*CT
-0CESS
DE3E20ME1T
roduct
Trades
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Georgia Tech
School of Aerospace EngineeringCC012314035ppt
Typical System @ife Cycle Cost
Cumulative
Percent
of LCC
Production# Deployment#
Operations and Support%6MDPD 6 RRCon %$p
*
**
***
7008
948
408
248
08
Life Cycle Cost
:ctually %$pended
Life Cycle Cost%ffectively Rendered
;nc!angeale fora /iven Design
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School of Aerospace Engineering
-amifications of the ,uality -e$olution
Decisions made in the design process cost 6ery
little in terms of the o6erall prodct cost 8t ha6e
a ma>or effect on the cost of the prodct ality cannot 8e 8ilt into a prodct nless it is
designed into it
The design process shold 8e condcted so as to
de6elop 9ality cost5competiti6e prodcts in the
shortest time possi8le
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Georgia Tech
School of Aerospace Engineering
Design rocess aradigm Shift(Research Opportunities in Engineering Design, NSF Strategic lanning !or"shop Final
Report, April #$$%)
100%
50%
0%
Todays Design ProcessFuture Design Process
KnowledgeAboutDesign
DesignFree
dom
CostComm
itted
Concept
Preliminary
Design
Analysisand DetailDesign
PrototypeDevelopment
Redesign ProductRelease
Aparadigm shiftis nder'ay thatattempts to change the 'ay complexsystems are 8eing designed
Emphasis has shifted from design forperformanceto design foraffordability, 'here afforda8ility is
defined as the ratio of systemeffectiveness to system cost +profit
System Cost - Performance Tradeoffsmst 8e accommodated early
Donstream !noledgemst 8e8roght 8ac2 to the early phases ofdesign for system level tradeoffs
The design +reedom cr6e mst 8e"ept openntil !noledgeabletradeoffscan 8e made
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Georgia Tech
School of Aerospace Engineering
Static $s Dynamic roducts
Some prodcts are static, in that the changes intheir design concept ta2e place o6er a long time
periodB rather, incremental changes occr at thes8system and component le6els (most air6ehicles are static)
3ther prodcts are dynamic, li2e
telecommnications systems and soft'are, thatchange the 8asic design concept fairly fre9entlyas the nderlying technology changes (a6ionicsand mission e9ipment : soft'are are dynamic)
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Georgia Tech
School of Aerospace Engineering
Simplified Design Process
Definition of the Pro8lem
&athering 0nformation
&eneration of Alternati6e Soltions
E6alation of Alternati6es
Commnication of the Reslts
G i
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Georgia Tech
School of Aerospace Engineering
Georgia Tech Generic ID Methodology
COMPUTER-INTEGRATED ENVIRONMENT
P
R
O
D
U
C
T
D
E
S
IG
N
D
R
IV
E
N
P
R
O
C
E
S
S
D
E
S
IG
N
DR
IV
E
N
REQUIREMENTS& FUNCTIONALANALYSIS
SYSTEM DECOMPOSITION&FUNCTIONAL ALLOCATION
SYSTEM SYNTHESISTHROUGH MDO
SYSTEM ANALYSIS&
CONTROL
ESTABLISHTHE NEED
DEFINE THE PROBLEM
ESTABLISHVALUE
GENERATE FEASIBLEALTERNATIVES
EVALUATEALTERNATIVE
7 M&P TOOLS ANDQUALITY FUNCTIONDEPLOYMENT (QFD)
ROBUST DESIGNASSESSMENT &OPTIMIZATION
ON-LINE QUALITYENGINEERING &STATISTICALPROCESS
MAKE DECISION
SYSTEMSENGINEERING METHODS
QUALITYENGINEERING METHODS
TOP-DOWN DESIGNDECISION SUPPORT PROCESS
G i T h
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School of Aerospace Engineering
Detailed Description of Design roblems!Morris Asimo."s Morphology of design#
Phase 0. Conceptal Design
Phase 00. Em8odiment Design (Preliminary Design)
Phase 000. Detail Design Phase 0. Planning for #anfactre
Phase . Planning for Distri8tion
Phase 0. Planning for se
Phase 00. Planning for Retirement of the Prodct
G i T h
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School of Aerospace Engineering
Discrete Steps in Engineering Design rocess
G i T h
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School of Aerospace Engineering
Design Depends on Indi$idual 4ho Defines roblem
G i T h
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Georgia Tech
School of Aerospace Engineering
Classification of roducts 'ased on Mar(et
latform roduct
1 0s 8ilt arond a preexisting technological s8systems, e.g. Apple
#acintosh operating systems
1 0s similar to a technology5psh prodct
Process50ntensi6e Prodcts
1 #anfactring process places strict constraints on the properties of
the prodct
1 Examples are atomoti6e sheet, steel, food prodcts,semicondctors chemicals and paper
Cstomi4ed Prodcts
1 ariations in configration and content created in response to a s
G i T h
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Georgia Tech
School of Aerospace Engineering
The Total Materials Cycle
G i T h
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School of Aerospace Engineering
The Systems Engineering rocess
Process Input
*Customer +eedsuirements
- Missions - Measures of %ffectiveness
- %nvironments
- Constraints*Tec!nology ?ase*Output Re>uirements from Prior
Development %ffort*Program Decision Re>uirements*Re>uirements :pplied T!roug!
Specifications and Standards
Requirements Analysis*:naly@e Missions 6 %nvironments*,dentify Functional Re>uirements*Defineuirement
Functional Analysis/Allocation*Decompose to Lo(er-Level Functions*:llocate Performance 6 Ot!er Limiting Re>uirements to
:ll Functional Levels*Define
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Georgia Tech
School of Aerospace EngineeringCC01231B315ppt
Systems Engineering, 0ts Prpose
To satisfy a mission need 'ith a system
that is cost effecti6e, operationallysita8le, and operationally effecti6e.
Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231B345ppt
Systems Engineering 38>ecti6es Translate cstomer needs into 8alanced systems8system
design re9irements and prodct
0ntegrate technical inpts of the entire de6elopmentcommnity and all technical disciplines into a coordinated
program effort Transition ne' technologies into prodct and a8atement
program
Ensre the compati8ility of all fnctional and physical
interfaces erify that the prodct meets the esta8lished re9irements
Condct a formal ris2 management and
Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231925ppt
7hat 0s a System= A system is a collection of components
(s8systems) that
10nteract 'ith one another
1a6e emergent capa8ilities 5 capa8ilities a8o6e
and 8eyond 'hat the same collection of
components 'old if they did not interact
10nteracting components implies architectre
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Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231B3B5ppt
System Element Constitents E9ipment ard'are1 #ission hard'are
1 &rond e9ipment
1 #aintenance e9ipment
1 Training e9ipment
1 Test e9ipment
1Special e9ipment
1 Real Property
1 Spares
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Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231025ppt
Systems Engineering rinciples Apply to All Acquisition
hases at All 2e$els of the Engineering 5ierarchy
Levels in t!e
System .ierarc!y
C%D - Concept %$ploration
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Georgia Tech
School of Aerospace EngineeringCC01231B975ppt
Systems
Engineering
Process
Systems Engineering 0n 0PD
ProductTeamsProductTeams
,PD
ConcurrentDevelopmentConcurrentDevelopment
Systems
%ngineering
Process
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Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231B905ppt
System Element Constitents (cont.)
Personnel
1 Training
1 Tas2s
1Fm8er
1 Types and s2ills
Data
1 Parts #anals1 #aintenance #anals
1 3perating #anals
Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231905ppt
Systems Thin2ing
Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231975ppt
Roles of Systems EngineersG Re9irements 3'ner System Designer
System Analyst
alidationerification Engr
@ogistics3ps Engineer
&le Among S8systems
* Customer ,nterface* Tec!nical Manager
* ,nformation Manager
* Process %ngineer
* Coordinator
* Classified :ds S%
SourceE T(elve Roles of Systems
%ngineers# Sara! S!eard;RLE (((5soft(are5org
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Georgia Tech
School of Aerospace EngineeringCC01231925ppt
7hat 0s a System= A system is a collection of components
(s8systems) that
10nteract 'ith one another
1a6e emergent capa8ilities 5 capa8ilities a8o6e
and 8eyond 'hat the same collection of
components 'old if they did not interact
10nteracting components implies architectre
Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC0123195ppt
Examples of Systems Aircraft engine 6s a collection of parts Aircraft 'ith engines and a6ionics
Air traffic control 'ith aircraft, airfields,radars, controllers, CCS
Air transportation 'ith air traffic control,
airlines, passengers, cargo, maintenance,pic2p and deli6ery
Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231915ppt
#ore Complex Systems
Systems of SystemsG 0ndi6idal systems can operate on their o'n
Systems of systems not o'ned andcontrolled as a 'hole 8y single entity
G#ar2 #aier, !Architecting Principles for Systems5of5
Systems$, Hornal of the 0nternational Concil onSystems Engineering, ol 0, -/
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Georgia Tech
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Georgia Tech
School of Aerospace EngineeringCC01231935ppt
Technical Director 0s the Systems
Thin2er 0f not, o8>ecti6es, approaches, and
decisions 'ill not reflect systems
thin2ing Technical Directors 'ho donect
Georgia Tech
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g
School of Aerospace EngineeringCC01231995ppt
7hy 0s Systems Thin2ing
&ood= 0ntracta8le pro8lems often ha6e soltions in
the design space of the larger system
Soltions in the larger systems space are oftenless costly or less ris2y
0ntegration 'ith external systems areaddressed
early in the de6elopment
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g
School of Aerospace EngineeringCC0123195ppt
A Dose of Reality Separate trash collections for recyclea8le'old do8le the cost
#ar2et for recycled ne'spaper andalminm
cans 'as satrated
nsold recyclea8les 'old ha6e to 8estored 55 at additional cost
Georgia Tech
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g
School of Aerospace EngineeringCC01231B005ppt
Starting to Thin2 Systems 7ho crrently collects trash=
+rom 'hom=
7hat is done 'ith the trash=
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g
School of Aerospace EngineeringCC01231B025ppt
The @and +ills as Part of the
System I-JG per ton to dmp trash in the land fill
Expected to reach I%* per ton in -K years
@and fills charge I-K* per ton in Fe'
?or2
Gee, maybe we should think aboutconserving the land fills?
Georgia Tech
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g
School of Aerospace EngineeringCC01231B05ppt
A Systems Soltion T'o collections per 'ee213ne for recyclea8les
13ne for non5cyclea8le trash
Slight increase in fees for storingrecyclea8les
Market demand of recycled paperand aluminum increase soared in 5years
Georgia Tech
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School of Aerospace EngineeringCC01231B015ppt
Conse9ences of Systems
Thin2ing The original o8>ecti6e (sa6ing
resorces)
'as satisfied Crrent costs 'ere contained
+tre cost containment made theslightincrease salea8le to the p8lic
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Dieter Chapter 67
"eed Identification and Problem Definition
3f all the steps in the engineering design process, pro8lemdefinition is the most important
;efore the Pro8lem5Definition Step" Design pro>ects
commonly fall into one of fi6e types"1 ariation of an existing prodct
1 0mpro6ement of an existing prodct
1 De6elopment of a ne' prodct for lo'56olme prodction rn
1 De6elopment of a ne' prodct for mass prodction
1 3ne5of5a52ind5 design
0dentifying Cstomer Feeds
&athering 0nformation from Cstomers
Georgia Tech
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Dieter Chapter 67
"eed Identification and Problem Definition
Constrcting a Sr6ey 0nstrment
;enchmar2ing
Cstomer Re9irements
ality +nction Deployment
Prodct Design Specification1 The 8asic control and reference docment for the design and
manfactre of the prodct
1 0n5se Prposes and #ar2et1 +nctional Re9irments
1 Corporate Constraints
1 Social, Political and @egal Re9irements
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resentation 0utline
Synthesis and Si4ing of Aerospace ehicles
#ane6era8ility and Agility Considerations
for Aerial ehicles
Atonomos ehicle Considerations
Smmary and Conclsions
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Synthesis and Si8ing of Aerial 3ehicles
+or Aerial ehicles Synthesis and Si4ing pro6ides the Closre
8et'een #ission Re9irements and &eometric Configration
Soltions
A +el and ThrstPo'er ;alance Approach is sed 'hich
allo's for analytical design optimi4ation (min. &7, etc.)throgh the copling of a fe' critical design parameters
(+7Laspect ratio, 'ing loadingB R7Ldis2 loading)
#ane6era8ility and Agility can 8e related to Energy
Principles (differences 8et'een ThrstPo'er A6aila8le and
ThrstPo'er Re9ired), andling alities and the design of
the +lightControl System
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Maneu$erability and Agility
Considerations for Aerial 3ehicles
Fied !ing Fighter Aircraftnormally ha6e a good high speed
capa8ility, good mane6era8ility at normal com8at speeds (medim to
high s8sonic and transonic speeds), high specific excess po'er, good
to excellent a6ionics, and the a8ility to employ gns and a 'ide range
of air5to5air missiles. To achie6e these capa8ilities, their optimm
mane6ering speeds are sally rather high, impacting on lo' speed
mane6era8ility
Rotary 7ing Aircraft ha6e excellent lo' speed capa8ility de to the
rotor h8 control moments 'hich pro6ides excellent control po'er in
any axix. This allo's rotary 'ing aircraft to fly Fap5of5the5Earth andstress aggressi6e concealed mo6ement to ta2e fll ad6antage of
mas2ing pro6ided 8y trees and terrain and attac2ing from a position of
ad6antage at maximm standoff range
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School of Aerospace Engineering
Summary and Conclusions Aerial ehicle Design and Performance is highly
dependent on the #ission identified and se of a +el and
ThrstPo'er Synthesis Approach
+or high speed, high altitde, high mane6ering attac2
missions, sch as Sppression of Enemy Air Defense(SEAD), +ixed 7ing Aerial ehicle are the Choice
+or lo' speed, lo' altitde, high agility(along 'ith
6ertical ta2eoff and landing (T3@)capa8ility)
reconnaissance and attac2 missions, sch as r8an7arfare, Rotary 7ing Aerial ehicles are the Choice
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Technological Inno$ation and The Design rocess
The ad6ancement of technology has three phases"
1 'nention" The creati6e act 'here8y an idea is concei6ed
1 'nnoation" The process 8y 'hich an in6ention or idea is 8roght
into sccessfl practice and is tili4ed 8y the economy1 Diffusion" The sccessi6e and 'idespread initiation of sccessfl
inno6ation
The technological inno6ation acti6ity can considered to 8e"
0dent. 3f
#2t Feed
Prodct
idea
Pilot
lot
Trial
sales
Commerc
ExploitationDe6elop
ment
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Societal Considerations in Engineering
Characteristics of an En6ironmentally
Responsi8le Design
+i6e roles of go6ernment in interacting 'ithtechnology
Technology 0dentification, E6alation and
Selection (T0ES)
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Dieter7 Chapter :
Team 'eha$ior and Tools A team is a small nm8er of people 'ith complementary s2ills 'ho are
committed to a common prpose, performance goals, and approach for 'hichthey hold themsel6es mtally acconta8le
Differences 8et'een a 'or2ing grop and a team
7or2ing &rop Team
5Strong, clearly focsed leader 50ndi6idal : mtal acconta8ility
5The grop,s prpose is the 5 Specific team prpose that the team
Same as the 8roader org.msn. 0tself de6elops
5 0ndi6idal 'or2 prodcts 5 Collecti6e 'or2 prodcts
5 Rns efficient meetings 5 Encorages open5ended discssion
and acti6e pro8lem5sol6ing meetings
5 #easres its effecti6eness 5 #easres performance directly 8y
indirectly 8y its inflence assessing collecti6e 'or2 prodcts
5Discsses,decides and delegates 5 Discsses, decides and does real 'or2
together
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Dieter7 Chapter :
Team 'eha$ior and Tools 7hat 0t #eans to 8e an Effecti6e Team #em8er
1 Ta2e responsi8ility for the sccess of the team
1 ;e a person 'ho deli6ers on commitments
1 ;e a contri8tor to discssions
1 &i6e yor fll attention to 'home6er is spea2ing and demonstrate this 8y as2ing helpfl9estions
1 De6elop techni9es for getting yor message across to the team1 @earn to gi6e and recei6e sefl feed8ac2
The follo'ing are characteristics of an effecti6e team"1 Team goals are as important as indi6idal goals
1 The team nderstands the goals and is committed to achie6ing them
1 Trst replaces fear and people feel comforta8le ta2ing ris2s
1 Respect, colla8oration and open5mindedness are pre6alent
1 Team mem8ers commnicate readilyB di6ersity of opinions are encoraged
1 Decisions are made 8y consenss and ha6e the acceptance and spport of the mem8ers ofthe team
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Dieter7 Chapter :
Team 'eha$ior and Tools
TEA# R3@ES" 7ithin a team mem8ers assme differentroles in addition to 8eing an acti6e team mem8er
TEA# D?FA#0CS"Stdents of team 8eha6ior ha6eo8ser6ed that most teams go throgh fi6e stages of
de6elopment E++ECT0E TEA# #EET0F&S" Stdents 'ho complain
a8ot design pro>ects ta2ing too mch time often are reallyexpressing their ina8ility to organi4e their meetings andmanage their time effecti6ely
PR3;@E#S 70T TEA#S" A 'ell5fnctioning teamachie6es its o8>ecti6es 9ic2ly and efficiently in anen6ironment that indces energy and enthsiam
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Dieter7 Chapter :
Team 'eha$ior and Tools
PR3;@E# S3@0F& T33@S
T0#E #AFA&E#EFT
P@AFF0F& AFD SCED@0F&
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Dieter7 Chapter ect them toan e6alation scheme to determine the 8est concept or
small s8set of 8est concepts +inally, a decision process 'ill 8e sed to decide on the
8est concept to de6elop into the final design
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Dieter7 Chapter @
Embodiment !reliminary# Design #any .S. 'riters di6ide the design process into % phases"
1 Conceptal Design
1 Preliminary (Em8odiment) Design
1 Detail Design
3thers call em8odiment design !analytical design$ 8ecase it is the
design phase 'here most of the detailed analysis and calclation occrs Dieter adopts the terminology conceptal design, em8odiment design,
and detail design 8ecase they seem to 8e more descripti6e of 'hatta2es place in each of these design phases
#o6ing the setting of dimensions and tolerances into em8odiment
design (from detail design) is in 2eeping 'ith the crrent trend fortili4ing CAE so as to mo6e the decision ma2ing as early as possi8le inthe desing process to compress the prodct de6elopment cycle
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Dieter7 Chapter @
Three different forms of design"1 Rotine design" the attri8tes that define the design and the
strategies and methods for attaining them are 'ell 2no'n
1 0nno6ati6e design" not all attri8tes of the design may 8e 2no'n8eforehand, 8t the 2no'ledge 8ase for creating the design is2no'n
1 Creati6e design" neither the attri8tes of the design nor thestrategies for achie6ing them are 2no'n ahead of time
The Conceptal design phase is most central to inno6ati6edesign
At the opposite pole is selection design or catalog design,'hich is more central to rotine design
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Dieter7 Chapter @roduct Architecture
Prodct architectre is the arrangement of the physical elements of a prodct to
carry ot its re9ired fnctions 0t is in the Em8odiment design phase that the layot and architectre of the
prodct mst 8e esta8lished 8y defining 'hat the 8asic 8ilding 8loc2s of theprodct shold 8e in terms of 'hat they do and 'hat their interfaces 'ill 8e8et'een each other. Some organi4ations refer to this assyste)*leel design
There are t'o entirely opposite styles of prodct architectre, modlar and
integral"1 #odlar" components (chn2s) implement only one or a fe' fnctions and theinteractions are 'ell defined
1 0ntegral" implementation of fnctions ses only one or a fe' components (chn2s)leading to poorly defined interactions 8et'een components (chn2s)
0n integral prodct achitectres components perform mltiple fnctions
Prodcts designed 'ith high performance as a paramont attri8te often ha6ean integral architectre
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Dieter7 Chapter @roduct Architecture
+or step process for esta8lishing the prodct architectre
1 Create a schematic diagram of the prodct (++;D, Schematic
;loc2 Diagram)
1 Clster the elements of the schematic (DS#, De#A0D)1 Create a rogh geometric layot (%56ie' dra'ing)
1 0dentify the fndamental and incidental interactions
(0nterrelationship Diagraph, Compati8ility #atrix)
SEE EQA#P@ES +R3# TEQT
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Dieter7 Chapter @Configuration Design
Steps in starting Configration design"1 Re6ie' the PDS
1 Esta8lish the spatial constraints that pertain to th prodct or thes8assem8ly 8eing designed. #ost ha6e 8een set 8y the prodctarchitectre
1 Create and refine the interfaces or connections 8et'een components1 #aintain fnctional independence in the design of an assem8ly or
component
1 Ans'er the follo'ing 9estions"
Can the part 8e eliminated or com8ine 'ith another part=
Can a standard part or modle 8e sed &enerally, the 8est 'ay to get started 'ith configration design is to >st
start s2etching alternati6e configrations of a part
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Dieter7 Chapter @arametric Design
0n configration design the emphasis 'as on starting 'ith
the prodct architectre and then 'or2ing ot the 8est
form for each component
0n parametric design the attri8tes of parts identified in
configration design 8ecome the design 6aria8les forparametric design
A design 6aria8le is an attri8te of a part 'hose 6ale is
nder the control of the designer
Ro8stness means achie6ing excellent performance nder
the 'ide range of conditions that 'ill 8e fond in ser6ice
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Dieter7 Chapter Modeling and Simulation
The Role of #odels in Engineering Design
1 Descripti6e model
1 Predicti6e model
1 Static or dynamic1 Deterministic or pro8a8ilistic
1 0conic5analog5sym8olic
1 Simlation
1The Prototype
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Dieter7 Chapter Modeling and Simulation
Dimensional Analysis
1 ;c2ingham Pi Theorem
Similitde and Scale #odels1 Scale models
1 &eometric similarity
#odel dimension scale factor x prototype dimension
1 Static similarity5same portion as geometric dim nder cons. stress1 inematic similarity5 ratio of time proportionality
1 Dynamic similarity5 fixed ratio of forces
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Dieter7 Chapter Modeling and Simulation
Simlation1 +inite5Difference #ethod
A method of approximate soltion of partial differential e9ations
1 #onte Carlo #ethod A 'ay of generating information for a simlation 'hen e6ents occr in a
random 'ay
1 &eometric #odeling on the Compter +rom it initiation,CAD has promised K important 8enefits to the
engineering design process
1 Atomation of rotine design tas2s
1 A8ility to design in %D
1 Design 8y Solid #odeling1 Electronic transfer of the design d8 to manf (CADCA#)
1 A paperless design process
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Dieter7 Chapter Modeling and Simulation
Srface #odeling
#ethods of &enerating Solids
Constraint5;ased #odeler and +eatres
+inite5Element Analysis
1 Types of Elements
1 Steps in the +EA Process
Preprocessing" &eometry, #atl constit reln, +E mesh, ;ndy Conds
Postprocessing" Data interpret., Error estim., Design optim
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Dieter7 Chapter Modeling and Simulation
Compter isali4ation
1 Dynamic Analysis
1 0nteracti6e Prodct Simlation
Rapid Prototyping
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Dieter7 Chapter BMaterials Selection and Materials in Design
Relation of #aterials Selection to Design1 An incorrectly chosen material can lead not only to failre of the part
8t also to nnecessary life5cycle cost
1 Selecting the 8est material for a part in6ol6es more than selecting amaterial that has the properties to pro6ide the necessary performance in
ser6iceB it is also intimately connected 'ith the processing of thematerial into the finished part (+ig. /.-)
1 As design proceeds from concept design, the material and processselection 8ecomes more detailed
1 +igre /. compares the design methods and tools sed at each designstage 'ith the materials and processes selection
1 Ths, material and process selection is a progressi6e process ofnarro'ing from a large ni6erse of possi8ilities to a specific materialand process selection
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Dieter7 Chapter BMaterials Selection and Materials in Design
Performance Characteristics of #aterials1 The performance or fnctional re9irements of material sally is
expressed in terms of physical, mechanical, thermal, electrical, orchemical properties
1 #aterial properties are the lin2 8et'een the 8asic strctre and
composition of the material and the ser6ice performance of the part(+igre /.%)
1 7e can di6ide strctral engineering materials into metals, ceramics,and polymersB +rther di6ision leads to the categories of elastomers,glasses, and compositesB +inally, there is the technology dri6ingclass of electronic, magnetic, and semicondctor materials
1 The chief characteristics of metals, ceramics, and polymers are gi6enin Ta8le /.-
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Materials Selection and Materials in Design Performance Characteristics of #aterials
1 The ltimate goal of materials science is to predict ho' to impro6e the properties
of engineering materials 8y nderstanding ho' to control the 6arios aspects ofstrctre
1 +igre /.M relates 6arios dimensions of strctre 'ith typical strctral elements
1 The first tas2 in materials selection is to determine 'hich material properties arerele6ant to the sitation
1 +igre /.K sho's the relations 8et'een some common failre modes and themechanical properties most closely related to the failres
1 The material properties sally are formali4ed throgh specifications"Performance and Prodct specifications
1 Ta8le /. pro6ides a fairly complete listing of material performancecharacteristics
1 +igre /.N illstrates the generic tree that is de6eloped 8y expanding the categoryof fatige properties
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Dieter7 Chapter BMaterials Selection and Materials in Design
The #aterials Selection Process1 The pro8lem is not only often made difficlt 8y insfficient or
inaccrate property data 8t is typically one of decision ma2ing in theface of mltiple constraints 'ithot a clear5ct o8>ecti6e fnction
1 A pro8lem of materials selection sally in6ol6es one of t'o differentsitations
Selection of the materials for a ne' prodct or design
Ree6alation of an existing prodct or design to redce cost,increase relia8ility, impro6e performance, etc.
1 0t generally is not possi8le to reali4e the fll potential of a ne' materialnless the prodct is redesigned to exploit 8oth the properties and the
manfactring characteristics of the material1 0n other 'ords, a simple s8stittion of a ne' material 'ithot changing
the design rarely pro6ides optimm tili4ation of the material
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Dieter7 Chapter BMaterials Selection and Materials in Design
#aterials selection for a ne' prodct or ne' design" The steps that mst 8e
follo'ed are"1 Define the fnctions that the design mst perform
1 Define the manfactring parameters
1 Compare the needed properties and parameters 'ith large data8ase
1 0n6estigate the candidate materials in more detail
1 De6elop design data andor a design specification
#aterials s8stittion in an existing design1 Characteri4e the crrently sed material in terms of performance, manfactring
re9irements, and cost
1 Determine 'hich characteristics mst 8e impro6ed for enhanced prodct fnction
1 Search for alternati6e matls : processing rotes
1 Compile a short list of matls : processing rotes and se these to estimate the costs
of manfactred parts1 E6alate the reslts of Step M : ma2e a recommendation for a replacement material
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Dieter7 Chapter BMaterials Selection and Materials in Design
Sorces of 0nformation on #aterials Properties1 Conceptal Design
Typical material selection references, sch as Ash8y scheme
1 Em8odiment (Preliminary) Design Design decisions are 8eing made on the layot and si4e of parts and components
Design calclations re9ire materials properties for a narro'er class of materials 8t
specific to a particlar heat treatment or manfactring process These data are typically fond in hand8oo2s and compter d8s.
1 Detail Design ery precise data is re9ired
This goes 8eyond >st material properties to inclde information on manfactra8ility,cost, the experience in other applns, a6ail in the si4es and forms needed, and isses ofrepeat. of properties : A
T'o often o6erloo2ed factors are 'hether the manfactring process 'ill prodcedifferent properties in different directions in the part, and 'hether the part 'ill containa detrimental state of residal stress after manfactre
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pMaterials Selection and Materials in Design
Economics of #aterials
1 ltimately the decision on a particlar design 'ill come do'n to a trade5off8et'een performance and cost
1 7here performance doesn
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pMaterials Selection and Materials in Design
#ethods of #aterials Selection1 There is no method or small nm8er of methods of materials selection that has
e6ol6ed to a position of prominence
1 Since the final choice is a trade5off 8et'een cost and performance (properties),it is logical to attempt to express that relation as careflly as possi8le
1 +igre /.-* sho's the costs of s8stitting light'eight magterials to achie6e'eight sa6ing (fel economy) in atomo8iles
1 0t is important to reali4e that the cost of a material expressed in dollars per
pond may not al'ays 8e the most 6alid criterion
1 Total @@C is the most appropriate cost to consider
1 Consideration of factors 8eyond >st the initial materials cost leads to relationsli2e the relation sho'n in +igre /.--
1 A classic sitation regarding cost is the choice 8et'een t'o or more materials'ith different initial costs and different expected li6es. This is a standard
pro8lem in the field of engineering economy (See Chap. -%)
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Dieter7 Chapter BMaterials Selection and Materials in Design
Selection 'ith Compter5Aided Data8ases
1 se of a #erit +actor approach similar to an 3EC
#aterial Performance 0ndices
1 A materials performance index is a grop of material properties'hich go6erns some aspect of the performance of a component
Decision #atrices
1 Pgh Selection #ethod
1 7eighted Property 0ndex #aterials Selection 8y Expert Systems
ale Analysis
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Dieter7 Chapter
Materials rocessing and Design
Role of Processing in Design1 Prodcing the design is a critical lin2 in the chain of e6ents that starts
'ith a creati6e idea and ends 'ith a sccessfl prodct in themar2etplace
1 A serios pro8lem has 8een the tendency to separate the design andmanfactring fnctions into separate organi4ational nits
1 #ore con6entional manfactring is di6ided into (-) processengineering, () tool engineering, (%) 'or2 standards, (M) plantengineering, and (K) administration and control
1 7e ordinary thin2 of modern engineering in terms of the atomoti6eassem8le line, 8t mass prodction manfactring systems accont for
less than K percent of metal pars manfactred1 The ma>or opportnity for greatly increasing manfactring
prodcti6ity in small5lot manfactre
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p
Materials rocessing and Design Classification of Manufacturing rocesses
1 Solidification (casting) processes
1 Deformation processes
1 #aterial remo6al or ctting (machining) processes
1 Polymer processing
1 Po'der processing
1 Hoining processing
1 eat treatment and srface treatment
1 Assem8ly processes
Types of rocess Systems
1 Ho8 shop 5 Assem8ly line1 ;atch 5 Continos flo'
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p
Materials rocessing and Design actors Determining rocess Selection
1 Cost of manfactre and life cycle cost1 antity of parts re9ired
1 Complexity 1 shape, form, si4e
1 #aterial
1 ality of part
1 A6aila8ility, lead time, and deli6ery schedle
Design for Manufacturability !DM#
1 D+# &idelines (#in tot of partsB Standardi4e compsB secommon parts across prodct linesB Design parts to 8e mltifcnlBDesign parts for ease of fa8.B A6oid too tight tolerancesB A6oidsecondary opnsB tili4e the special characteristics of processes)
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Dieter7 Chapter
Materials rocessing and Design
Design for Assem8ly (D+A)1 The assem8ly process consists of t'o operations, handling
follo'ed 8y insertion
1 There are three types of assem8ly, classified 8y the le6el ofatomation
1 A list of D+A gidelines are" #in. the tot. no. of parts
#in. the assem8ly srfaces
A6oid separate fasteners
#in. assem8ly direction
#ax. compliance in assem8ly
#in handling in assem8ly
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Dieter7 Chapter
Materials rocessing and Design
Early Estimation of #anfactring Cost
1 The decisions a8ot materials, shape, featres and tolerances that
are made in the em8odiment phase of design determine the
manfactring cost of the prodct
1 0t is not often possi8le to get large cost redctions once prodction
has 8egn 8ecase of the high cost of change at this stage of the
prodct life cycle
1 Therefore, 'e need a 'ay of identifying costly designs as early as
possi8le in the design process1 3ne 'ay is to inclde 2no'ledgea8le manf psnl on 0PT
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Dieter7 Chapter 9
Engineering Statistics = robability
A 8asic nderlying assmption of pro8a8ility theory is that itdeals 'ith random e6ents
A random e6ent is one in 'hich the conditions are sch thateach mem8er of the poplation F has an e9al chance of 8eingchosen
A special and precise system of langage and notation is sedin pro8a8ility theory
T'o e6ents A and ; are said to 8e independent if theoccrrence of either one has no effect on the occrrence of theother
T'o e6ents that ha6e no elements in common are said to 8emtally exclsi6e e6ents
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Dieter7 Chapter 9Engineering Statistics > Errors and Samples & requency
Distribution
The act of ma2ing any type of experimental o8ser6ation
in6ol6es t'o types of errors"
1 Systematic errors ('hich exert a nonrandom 8asis)
1 Experimental,or random, errors 7hen a large nm8er of o8ser6ations are made from a
random sample, a method is needed to characteri4e the
data
1 istograms,1 +re9ency Distri8tion
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Dieter7 Chapter 9Engineering Statistics > Measures of Central Tendency &
Dispersion
A fre9ency distri8tion can 8e descri8ed 'ith nm8ers
that indicate the central location of the distri8tion and
ho' the o8ser6ations are spread ot from the central
location (dispersion)1 Arithmetic mean, or a6erage
1 #ode and #edian
1 Standard De6iation
1 Range
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Dieter7 Chapter 9Engineering Statistics > Types of Distributions
Formal and @ognormal Distri8tions
1 #any physical measrements follo' the symmetrical, 8ell5shaped cr6e of thenormal, or &assian, fre9ency distri8tion
7ei8ll Distri8tion
1 7idely sed for many engineering pro8lems 8ecase of its 6ersatility, sincemany random 6aria8les follo' a 8onded, nonsymmetrical distri8tion, sch asfatige life of components
&amma Distri8tion1 sed to descri8e random 6aria8les that are 8onded at one end
Exponential Distri8tion
1 Special case of the gamma distri8tion for U -
Distri8tions for Discrete aria8les
1 The normal and other distri8tions discssed deal 'ith continos random
6aria8lesBho'e6er, there are important engineering pro8lems in 'hich therandom 6aria8le ta2es on only discrete 6ales
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Dieter7 Chapter 9Engineering Statistics > Sampling Distributions
The central pro8lem in statistics is relating the poplation
and the samples that are dra'n from it
This pro8lem is 6ie'ed from t'o perspecti6es"
1 7hat does the poplation tell s a8ot the 8eha6ior of the samples1 7hat does a sample or series of samples tell s a8ot the
poplation form 'hich the sample came
Distri8tion of Sample #eans
t Distri8tion Distri8tion of Sample ariances
+ Distri8tion
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Dieter7 Chapter 9Engineering Statistics > Analysis of 3ariance
7hen 'e ha6e three or more samples treatments 'e can
se a statistical procedre call the Analysis of ariance
(AF3A) 'hich is important in design of experiments
7ith AF3A 'e determine"1 The total spread of reslts 8et'een the different treatments
1 The spread of reslts 'ithin each treatment
3ne57ay Classification
T'o57ay Classification
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Engineering Statistics Statistical Design of E%periments
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Engineering Statistics > Statistical Design of E%periments The greatest 8enefit can 8e gained from statistical analysis 'hen the experiments are
planned in ad6ance so that data are ta2en in a 'ay that 'ill pro6ide the most
n8iased and precise reslts commensrate 'ith the desired expenditre of time andmoney
This can 8est 8e done throgh the com8ined efforts of a statistician and the engineerdring the planning stage of the pro>ect
Pro8a8ly the most important 8enefit from statistically designed experiments is thatmore information per experiment 'ill 8e o8tained than 'ith an nplannedexperimentation
A second 8enefit is that statistical design reslts in an organi4ed approach to thecollection and analysis of information
Still another ad6antage of statistical planning is the credi8ility that is gi6en to theconclsions of an experimental program 'hen the 6aria8ility and sorces ofexperimental error are made clear 8y statistical analysis
+inally, an important 8enefit of statistical design is the a8ility to disco6er
interactions 8et'een experimental 6aria8les
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Dieter7 Chapter 9Engineering Statistics > Statistical Design of E%periments
0n general, there are three classes of statistically designedexperiments1 ;loc2ing designs se 8loc2ing techni9es to remo6e the effect of
8ac2grond 6aria8les from experimental error
1 +actorial designs are experiments in 'hich all le6els of each factorin an experiment are com8ined 'ith all le6els of e6ery other factor
1 Response srface designs are sed to determine the empiricalfnctional relation 8et'een factors (independent 6aria8les) and theresponse (performance 6aria8le). The central composite design and
rotata8le designs are fre9ently sed for this prpose +actorial Design
+ractional +actorial Designs
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Dieter7 Chapter 9Engineering Statistics > -egressional Analysis
Regression analysis is the statistical techni9e for
esta8lishing sch relationships 8et'een t'o or more
6aria8les
1 +nctional relation" emphasis is on prediction1 Association" correlation 8et'een 6aria8les, 'hich 6ary >ointly
#ethod of @east S9ares
@inear #ltiple Regression Analysis
Fonlinear Regression Analysis @ineari4ation Transformation
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-is( -eliability and Safety
A hazard(nsafe condition) is the potential for hman,property, or en6ironmental damage
A ris" is the li2elihood, expressed either as a pro8a8ility or as afre9ency, of a ha4ard
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-is( -eliability and Safety7 robabilistic Approach to
Design
There are three typical approaches for incorporating
pro8a8ilistic effects in design
1 The se of a factor of safety
1 The se of the a8solte 'orst case design1 The se of pro8a8ility in design
The se of pro8a8ility in design
Pf P(W X Sy)
The relia8ility R is defined asR -5Pf
See Example in Text
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-is( -eliability and Safety7 robabilistic Approach to
Design
aria8ility in #aterial Properties
1 The mechanical properties of engineering materials exhi8it
6aria8ility
1 +ractre and fatige properties sho' greater 6aria8ility than do the
static tensile properties of yield strength and tensile strength
1 Conser6ati6e design 6ales for material properties are re9ired in
the design of minimm 'eight
Pro8a8ilistic Design
1 Re6ie' the illstrated example of a cran2 that mst spport asingle static load
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-is( -eliability and Safety7 robabilistic Approach to
Design
Safety +actor
1 The se of a safety factor is far simpler 8t 'ith mch less
information content
1 sing a safety factor is a form of !derating$ 8t the extent of
redction from the tre capacity is not 2no'n
A8solte 7orse Case Design
1 0n a8solte 'orse case (A7C) design the 6aria8les are set at either
the lo'est or largest expected 6ales
1 A7C design, li2e the se of safety factor, is an approach thatacconts for the statistical natre of the design en6ironment in a
deterministic 'ay
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Dieter7 Chapter 99-is( -eliability and Safety7 -eliability Theory
Relia+ilityis the pro8a8ility that a system, component, orde6ice 'ill perform 'ithot failre for a specified period oftime nder specified operating conditions
The discipline of relia8ility engineering 8asically is a stdy ofthe cases, distri8tion, and prediction of failre
Definitions1 ean life" The a6erage life of the nm8er of components pt on test or
in ser6ice, measred o6er the entire life cr6e ot to 'earot
1 ean ti)e +et-een failures (..F/0The sm of sr6i6al time (p time)for all of the components di6ided 8y the nm8er of failres
1 ean ti)e +et-een failures (.1F/0The mean time 8et'een t'osccessi6e component failres. #T;+ is similar to #TT+, 8t it isapplied for components or systems that are repaired
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Dieter7 Chapter 99-is( -eliability and Safety7 -eliability Theory
System Relia8ility
1 #ost mechanical and electronic systems comprise a collection of
components
1 The o6erall relia8ility of the system depends on ho' the indi6idal
components 'ith their indi6idal failre rates are arranged1 0t is o86ios that if there are many components exhi8iting series
relia8ility, the system relia8ility 9ic2ly 8ecomes 6ery lo'
1 A system in 'hich the components are arranged to gi6e parallel
relia8ility is said to 8e redndantB there is more than one
mechanism for the system fnctions to 8e carried ot1 0n a system 'ith fll acti6e redndancy all 8t one component may
fail 8efore the system failsB See Aircraft Example for partial redn.
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Dieter7 Chapter 99-is( -eliability and Safety7 -eliability Theory
#aintenance and Repair1 0f a failed component can 8e repaired 'hile a redndant component
has replaced it in ser6ice, then the o6erall relia8ility of the systemis impro6ed
1 0f components s8>ect to 'ear can 8e replaced 8efore they ha6efailed, then the system relia8ility 'ill 8e impro6ed
1 Pre6enti6e maintenance is aimed at minimi4ing system failre
1 Repairing a failed component in a series system 'ill not impro6ethe relia8ility, since the system is not operating
1 o'e6er, decreasing the repair time 'ill shorten the period dring'hich the system is ot of ser6ice
1 aintaina+ilityis the pro8a8ility that a component or system thathas failed 'ill 8e restored to ser6ice 'ithin a gi6en time
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Dieter7 Chapter 99-is( -eliability and Safety7 Design for -eliability
The design strategy sed to ensre relia8ility can fall8et'een t'o 8road extremes
1 +ail5safe approach
1 !the one5horse shay$ approach
1 A8solte 'orse5case approach T'o ma>or areas of engineering acti6ity determine the
relia8ility of an engineering system1 Pro6ision for relia8ility mst 8e esta8lished dring the earliest
design concept stage, carried throgh the detailed design
de6elopment, and many steps in manfactre1 3nce the system 8ecomes operational, it is imperati6e that
pro6ision 8e made for its contined maintenance dring its ser6ice
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Dieter7 Chapter 99-is( -eliability and Safety7 Methods and Techniques
+ailre #ode and Effects Analysis (+#EA)1 Team58ased methodology for identifying potential pro8lems 'ith
ne' or existing designs
+alt Tree Analysis (+TA)
1 A techni9e that pro6ides a systematic description of thecom8inations of possi8le occrrences in a system that can reslt infailre or se6ere accidents
Defects and +ailre #odes1 ard'are failre
1 Soft'are failre1 man failre
1 3rgani4ation failre
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Dieter7 Chapter 99-is( -eliability and Safety7 Design for Safety
Safety may 'ell 8e the paramont isse in prodct design
There are three aspects to design for safety
1 #a2e the prodct safe, i.e. design all ha4ards ot of the prodct
1 0f a8o6e not possi8le, then design in protecti6e de6ices1 0f Step cannot remo6e all ha4ards, then 'arn the ser of the
prodct 'ith appropriate 'arnings li2e la8els, flashing lights, and
lod sonds
&idelines for Design for Safety
1 ;e familiar 'ith these
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Economic Decision Ma(ing
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g The ma>or engineering infrastrctre that 8ilt this nation 1 the railroads,
ma>or dams, 'ater'ays, and air transportation 1 re9ired a methodology
for predicting costs and 8alancing them against alternati6e corses ofaction
#athematics of Time ale of #oney
Depreciation
Taxes
Profita8ility of 0n6estments 3ther Aspects of Pro8a8ility
0nflation
Sensiti6ity and ;rea25E6en Analysis
ncertainty in Economic Analysis
;enefit5Cost Analysis
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Cost E$aluation
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An engineering design is not complete ntil 'e ha6e a good idea of the cost re9ired to 8ildthe design or manfactre the prodct
Categories of Costs #ethods of De6eloping Cost Estimates
Cost 0ndexes
Cost5Capacity +actors
Estimating Plant Cost
Design To Cost
#anfactring Costs
ale Analysis in Costing
36erhead Costs
Acti6ity5;ased Costing
Prodct Profit #odel
@earning Cr6e
Cost #odels
@ife Cycle Costing
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y g
Considerations Primary Text Chapters
1 Chap N" Em8odiment Design
1 Chap J" #odeling and Simlation
1 Chap /" #aterials Selection : #aterials in Design
1 Chap " #aterials Processing : Design1 Chap -*" Engineering Statistics
1 Chap --" Ris2, Relia8ility, and Safety
1 Chap -%" Economic Decision #a2ing
1 Chap -M" Cost E6alation
Secondary Text Chapter
1 Chap -%" #odeling and Simlation